The use of a pair of telescoping members to form one long structure is well known in the art. Each member has a substantially hollow cross-section of similar shape, with one member being sized to slide at least partially into the other, thus forming an overlap joint. These members frequently find use in pole structures for electrical transmission line support. The members are designed to be easily transported to the site and quickly erected to form a strong, weather proof structure.
In a typical transmission pole structure, a pair of thin walled, concentric tubular members are joined at the erection site to form one extended pole. The joint, or splice, between the two tubes is secured by field welding around the joint circumference or by through bolts which pass through holes drilled in the tubular members.
Due to the nature of the service of these transmission pole structures, the individual tubular members are generally painted or galvanized before transportation to the erection site. Since field welding of the joint may compromise the galvanized or painted coating, allowing possible corrosion of the structure, the through bolt is presently the preferred method for locking the splice joint.
The use of a through bolt to lock a splice joint in a transmission pole structure requires individual fabrication of the through bolts for each type of transmission pole members, an expensive process which results in a large inventory of different length through bolts for the various types of structures. There is a need in this area for a device which may quickly lock a wide variety of transmission pole structures without welding and without compromising the protective paint or galvanizing.